package com.example.day0705;

/**
 * @author Lenovo
 */
public class StudentDemo {
    public static void main(String[] args) {
        Student s1 = new Student();
        s1.show();

        Student s2 = new Student("张三");
        s2.show();
        Student s3 = new Student(18);
        s3.show();
         Student s4 = new Student("李四", 20);
         s4.show();
    }
}
